[Bisphosphonate therapy in osteoporosis. Inhibition of trabecular perforation by aminobisphosphonate].

After many years of experience with bisophosphonates in the treatment of "tumor osteopathy" and Paget's disease, these substances have now also been approved for use in the treatment of osteoporosis. Owing to their high affinity for calcium hydroxyapatite, the bisphosphonates are deposited in the bony surface, and the aminobisphosphonates exert their effect at the site of active resorption via direct inhibition of active osteoclasts. As a result of this inhibition of the osteoclastic bone resorption, trabecular perforation is reduced and during the course of bone remodelling by the activity of the osteoblasts, boneformation occurs. In addition to an increase in bone density, both etidronate and alendronate have been shown to inhibit vertebral fractures in patients with osteoporosis. In addition, in patients with preexisting fractures, alendronate is able, at the same time, to lower the incidence of fractures of the femoral neck. With proper administration, the associated occasional gastrointestinal side effects can be avoided. The introduction of bisphosphonates into the treatment of osteoporosis is definitely an enrichment of the therapeutic spectrum in conjunction with the basic treatment comprising calcium, vitamin D, diet and physical measures.